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Cucumber and other Cucurbitaceae plants have a high transpiration rate and sensitivity to water deficit stress. Ascorbic acid (AsA) and gamma aminobutyric acid (GABA) participate in a variety of plant processes and increase plant resistance to different stresses. The current study was aimed to assess the efficacy of the foliar application of AsA (100, 200 and 300 mg l−1) and GABA (20 and 40 mM) on growth, physiological parameters and water use efficiency related properties of cucumber plants under deficit irrigation (DI) strategy (0, 25 and 50%). Results showed that the highest values of measured morphological properties were recorded in plants treated with GABA at 40 mM and AsA at 100 mg l−1. The highest water use efficiency was observed in plants sprayed with GABA at 40 mM. Also, foliar spraying of GABA at 40 mM was the best treatment to improve the free proline content of leaves and the activity of antioxidant enzymes under drought stress conditions. Findings of this study showed that foliar application of AsA and GABA can be a useful and inexpensive treatment to improve morphological, physiological and water use efficiency related properties of cucumber plant under water deficit stress.

In this study, the effect of different levels of nitrogen (N) and potassium (K) fertilizers on vegetative fresh bulb yield, quality and biochemical attributes of sweet fennel were investiga...

Some of the most cultivated commercial cultivars of asparagus are susceptible to abiotic stresses. Different species of asparagus plant are distributed in different regions of Iran which could be useful genetic resources for applying in asparagus breeding programs. The purposes of the current study were to evaluate morphological variation of A. azerbaijanensis accessions and drought tolerance assessment of Iranian asparagus in order to introduce superior accessions. Two different accessions of A. azerbaijanensis species were collected. A number of 30 plants were selected and 22 morphological traits were then evaluated. A factorial experiment based on completely randomized design was performed in order to drought tolerance assessment of 9 Iranian asparagus accessions. The average of spear length and diameter in Ahar and Makou plants were 48.94 cm and 4.70 mm, respectively. Based on results, plants of Ahar accession produced short and thick spears but on the other hand, Makou accession plants produced longer and thinner spears. Score 8 (80% similarity rate) was averagely chosen by panel members in terms of similarity rate of A. azerbaijanensis accessions spears taste to that of Mary Washington commercial cultivar. The highest percentage of seed germination was recorded in Baladeh and Gazanak accessions (71.66 and 70.83%, respectively). Baladeh accession showed the highest carotenoid content under drought stress conditions (0.43 mg g Fw− 1). Suitable size and delicious taste of spear in A. azerbaijanensis species has made it a suitable candidate for commercial cultivation and also improving spear characteristics by using selection method. Baladeh and Gazanak accessions could be introduced as superior accessions with high drought tolerance rate. High resistance rate of these accessions can be related to their ploidy level and distribution areas characteristics.

Purpose The main objective of the present study was to evaluate the effects of compost formulation made from agricultural by-products and thermal treatment of fresh mushrooms on the postharvest quality parameters. Methods Quail manure was evaluated as an alternative ingredient to the broadly used chicken manure for compost preparation. In addition, the treatment of fresh mushrooms by hot water to extend shelf-life was tested. Quality parameters including color (browning due to microbial activity), cap opening and the weight loss (senescence) were evaluated. Results The nature of the manure employed as base material in the substrate can affect the postharvest browning ratio of mushroom. However, no significant differences in Δb value, weight loss or cap opening were noticed between two different substrates during storage of harvested mushrooms. The cap opening ratio was further retarded while applying thermal treatment to the mushrooms at 55 °C. Conclusions The use of chicken manure as base material to prepare mushroom substrate reduces mushroom browning during storage compared to quail manure, although mushrooms from quail compost are whiter at picking. Postharvest treatment at 45 °C for 4 min was the best to minimize the weight loss.

Eggplant is one of the most popular and vital vegetable crops in the world. Various plant bio-regulators have been used in different crops to increase uptake of nutrients thereby leading to improvement in growth, flowering, fruit quality, storability and yield. The scope of this study was to evaluate the effects of calcium lactate and salicylic acid foliar application on growth parameters, physiological characteristics and shelf-life of eggplant fruit. Obtained results showed that the highest applied concentrations of calcium lactate (4 mM or 0.8 g l-1) and salicylic acid (1.5 mM or 0.2 g l-1) foliar application led to the highest values of measured growth parameters and yield. Applying of calcium lactate and salicylic acid foliar treatments could increase tissue firmness and ascorbic acid content of fruits. Foliar application of calcium lactate 4 mM (0.8 g l-1) and salicylic acid 1 mM (0.13 g l-1) was the best treatment to decrease percentage of fruit decay. In conclusion, our results showed that foliar application of calcium lactate and salicylic acid can be useful and inexpensive treatment to improve growth parameters, physiological characteristics and post-harvest properties of eggplant fruit

Conventionally, drought analysis has been limited to single drought category. Utilization of models incorporating multiple drought categories, can relax this limitation. A copula-based model is proposed, which uses meteorological and hydrological drought characteristics to assess drought events for ultimate management of water resources, at small scales, i.e., sub-watersheds. The chosen study area is a sub-basin located at Karkheh watershed (western Iran), with five raingauge stations and one hydrometric station, located upstream and at the outlet, respectively, which represent 41-year of data. Prior to drought analysis, time series of precipitation and streamflow records are investigated for possible dependency/significant trend. Considering semi-arid nature of the study area, boxplots are utilized to graphically capture the rainy months, which are used to evaluate the degree of correlation between streamflow and precipitation records via nonparametric correlations. Time scales of 3- and 12-month are considered, which are used to study vulnerability of early vegetation establishment and long-term ecosystem resilience, respectively. Among four common goodness of fit (GOF) tests, Anderson–Darling is found preferable for defining copula distribution functions through GOF measures, i.e., Akaike and Bayesian information criteria and normalized root mean square error. Furthermore, a GOF method is proposed to evaluate the uncertainty associated with different copula models using the concept of entropy. A new bivariate drought modeling approach is proposed through copulas. The proposed index named standardized precipitation-streamflow index (SPSI) unlike common indices which are used in conjunction with station data, can be applied on a regional basis. SPDI is compared with widely applied streamflow drought index (SDI) and standardized precipitation index (SPI). To assess the homogeneity of the dependence structure of SPSI regionally, Kendall-τ and upper tail coefficient relation is investigated for all stations located within the region. According to results, SPSI similar to nonparametric multivariate standardized drought index (NMSDI) was able to detect both onset of droughts dominated by precipitation as is similarly indicated by SPI and persistence of droughts dominated by streamflow as is similarly indicated by SDI. It also captures discordant case of normal period precipitation with dry period streamflow and vice versa. This makes SPSI a powerful tool for estimating a more practical and realistic drought condition. Finally, combination of severity–duration–frequency (SDF) of drought events through copulas resulted in SDF curves that can be used to obtain the recurrence of extreme droughts and assess drought related ecosystem failure or to aid in optimization of water resources allocation. Results indicated that the newly proposed index (SPSI) is able to represent two main characteristics of meteorological and hydrological drought (drought onset and persistency) and also providing an accurate estimation of the recurrence interval of extreme droughts. The procedures can be used to undertake proactive water resource management and planning to assure water security and sustainable agriculture and ecosystem survival for regions experiencing extreme droughts.

Electron transport chains (ETC) are drastically inactivated in chloroplasts of in vitro shootlets due to presence of carbon source in the growth media. This inactivation consequently creates limitations for in vitro studies on the role of chloroplasts in biotic and abiotic stresses. This research was carried out to evaluate reactivation of electron flow in chloroplasts ETC by elimination of carbon source and subsequent comparison of the effects of ETC inhibitors in the presence and absence of carbon source (i.e., sucrose) on the in vitro shootlets of apple rootstock, MM-111. All the tested ETC inhibitors, including uracil; glutaraldehyde, methyl viologen (MV) and DCMU triggered necrosis appearance on the in vitro apple shootlets exclusively on the carbon source-free media. Moreover, exposure of the in vitro shootlets to the various concentrations of ETC inhibitors demonstrated different severity of ETC inhibition by these inhibitors and their concentration-dependent effects on chloroplasts ETC. Uracil, the inhibitor of photosystem II, triggered the weakest shootlets necrosis, while DCMU exhibited no necrogenic effects at 50 mg/L and lower concentrations. MV, contrary to glutaraldehyde, did not have necrogenesis effects at 1 mg/L, but both of them caused sharp necrosis trigger on the shootlets as soon as 48–96 h after exposure to their effective concentrations. Evaluation of the shootlets H+-ATPase activity revealed that proton extrusion and pH decline in the growth media were mainly associated with the sucrose uptake by the shootlets, while no considerable pH decline observed in the presence of carbon source in the media. Finally, chloroplasts ETC activity of the shootlets was confirmed by higher percentage of O2 and less CO2 quantity in the atmospheres of the jars containing sucrose-free media, as well as by higher initial fluorescence (Fo) and maximum fluorescence (Fm) quenching parameters in the shootlets, in comparison with the sucrose-enriched condition.

Introduction Two of the most frequent procedures performed on infertile women are two-dimensional ultrasound (2DUS) and three-dimensional ultrasound (3DUS). Hysteroscopy is considered as the gold standard for evaluation of acquired endometrial lesions in infertile women; however, 3DUS is used as a noninvasive, less expensive, and reliable assessment method for evaluation of the intrauterine lesions in infertile women. We aimed to compare the diagnostic efficiency between 3DUS and hysteroscopy in the detection of lesions (polyps, submucous leiomyoma, and synechiae) in infertile women. Materials and methods In this prospective observational study, infertile women (n = 155) with indication of hysteroscopy were scheduled to undergo 3DUS prior to hysteroscopy from September 2010 to 2011. Women with suspected congenital uterine anomalies were excluded. The sensitivity and specificity values of 3DUS were compared with those of hysteroscopy. Hysteroscopy was used as the gold standard for diagnosis of intrauterine lesions in infertile women. Results Of the 155 women, 50 were found to have an intracavitary abnormality, 36 had polyps, 12 had myomas, and 7 had synechiae on hysteroscopic findings. Examination with 3DUS in the diagnosis of intrauterine lesions reached an accuracy of 94%, and 92.15 and 96.9% of sensitivity and specificity respectively. Positive predictive value (PPV) was 83.9%, and a negative predictive value (NPV) was 91.3% (LR+ = 10.75, LR+ = 0.065). Conclusion According to our results, 3DUS has a reliable diagnostic accuracy for intrauterine lesions, and it may limit unnecessary hysteroscopy in patients with normal results. How to cite this article Ahmadi F, Haghighi H, Ghahremani Z, Niknejad F, Akhbari F, Ramezanali F, Chehrazi M. Diagnostic Accuracy of Three-dimensional Ultrasonography in Detection of Endometrial Lesions compared with Hysteroscopy in Infertile Women. Donald School J Ultrasound Obstet Gynecol 2016;10(4):393-397.

Attempts were made to identify eight pathogenesis related (PR) genes (i.e., PR-1a, PR3-ch1, PR3-Ch2, PR3-Ch3, PR3-Ch4, PR3-Ch5, PR-5 and PR-8) from 27 genotypes of apple, quince and pear, which are induced in response to inoculation with the pathogen Erwinia amylovora, the causal agent of fire blight. Totally, 32 PR genes of different families were obtained, excepting PR3-Ch2 (amplified only in apple) and PR3-Ch4 (amplified only in apple and pear), the others were successfully amplified in all the genotypes of apple, quince and pear. Evolutionary, the genes of each family exhibited significant homology with each other, as the corresponded phylogenetic neighbor-joining-based dendrograms were taken into consideration. Meanwhile, according to the expression assay, it was deduced that the pathogen activity can significantly affect the expression levels of some selected PR genes of PR3-Ch2, PR3-Ch4, PR3-Ch5 and particularly Cat I in both resistant (MM-111) and semi-susceptible (MM-106) apple rootstocks. Lastly, it was concluded that the pathogen E. amylovora is able to stimulate ROS response, particularly using generation of hydrogen peroxide (H2O2) in both aforementioned apple rootstock.

Fire blight is an important disease of pome fruits, especially pears and quinces. Substitution of susceptible with tolerant cultivars is an economically and technically effective control method. Identifying tree traits associated with disease tolerance, may be helpful to screening and breeding programs, as well as genetic studies of resistance. Disease tolerance was evaluated in the national pear collection of SPII in two main categories of 8 and 20 indigenous commercial cultivars. The disease severity was evaluated using the USDA index in two successive epidemic years. 83 vegetative and reproductive traits were considered based on International Union for the Protection of New Varieties of Plants (UPOV) descriptor in all pears. Cultivars ‘Dar Gazi’ and ‘Tashkandi’ demonstrated the highest resistance level among tested cultivars. Among evaluated traits, 15 out of 83 were correlated with disease resistance. Among tree traits that were correlated to the disease resistance, 7 traits were from flowers, the main entrance of pathogen into the host. Low branching, fruit ripening variation, shape of leaf apex and number of buds in the clusters demonstrated the strongest correlation with disease tolerance; followed by other traits such as sepal color of immature fruits, fruit juiciness, size of flower and leaf, and pedicle length. The significant correlated traits could be useful as morphological or physiological markers in breeding programs.

Research has demonstrated that the interaction between HrpN and the mitochondrial electron transport chain (ETC) causes the generation of the reactive oxygen species (ROS) and an oxidative burst in host cells. To date, the interaction between bacterial infection and host chloroplasts has not been studied. This research was carried out to study the role of chloroplast ETC in this interaction in two host species, apple (Malus x domestica Borkh.) and pear (Pyrus communis L.). Accordingly, apple rootstocks, 'MM-111' (tolerant) and 'MM-106' (susceptible) and pear cultivars, 'Harrow Sweet' (tolerant) and 'Spadona' (susceptible) were micropropagated. Uracil was used as chloroplast ETC inhibitor at the presence and absence of sucrose to compare effects of ETC inhibition both in low and high photosynthesis activity of in vitro shootlets. E. amylovora Ea273 was used for basal inoculation of shootlets and the disease progression was studied by establishing necrosis indices. The in vitro system was initially optimized on 'MM-111' apple. Shoots were exposed to uracil prior to inoculation, in the absence of sucrose to separated herbicide effects of uracil from bacterial necrosis in ETC activated chloroplasts. Uracil on activated ETC chloroplasts and in the presence of E. amylovora, delayed necrosis appearance, the visible symptoms of oxidative burst in shootlets of both hosts. Uracil presence significantly reduced ROS generation during pathogen-host interaction, and ROS generation corresponded with the appearance of necrosis in all cultivars.

Erwinia amylovora is a necrogenic bacterium, causing the fire blight disease on many rosaceous plants. Triggering oxidative burst by E. amylovora is a key response by which host plants try to restrain pathogen spread. Electron transport chain (ETC) of chloroplasts is known as an inducible source of reactive oxygen species generation in various stresses. This research was performed to assess the role of this ETC in E. amylovora–host interaction using several inhibitors of this chain in susceptible and resistant apple and pear genotypes. All ETC inhibitors delayed appearance of disease necrosis, but the effects of methyl viologen, glutaraldehyde, and DCMU were more significant. In the absence of inhibitors, resistant genotypes showed an earlier and severe H2O2 generation and early suppression of redox dependent, psbA gene. The effects of inhibitors were corresponding to the redox potential of ETC inhibitory sites. In addition, delayed necrosis appearance was associated with the decreased disease severity and delayed H2O2 generation. These results provide evidences for the involvement of this ETC in host oxidative burst and suggest that chloroplast ETC has significant role in E. amylovora–host interaction.